package aco;

public class Timer {

    private static long startTime;

    // virtual and real time of day are computed and stored to allow at later time the computation of the elapsed time
    static void start_timers()
    {
    	startTime = System.currentTimeMillis();
    }

    // return the time used in seconds (virtual or real, depending on type)
    // 计算当前时间距离开始时间过去了多久
    static double elapsed_time()
    {
    	return (System.currentTimeMillis() - startTime) / 1000.0;
    }
}
